Little change to Isaac, but storm poses a serious storm surge threat

By: Dr. Jeff Masters , 3:25 PM GMT on August 27, 2012

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Tropical Storm Isaac has changed little in strength or organization this morning, as the storm heads northwest at 14 mph towards the Central Gulf Coast. There are two hurricane hunter aircraft in the storm, and Isaac's central pressure held steady at 989 mb at the 8:30 am and 9:15 am center fixes. Top surface winds remain near 65 mph. Infrared and visible satellite loops show that Isaac is a very large storm, but isn't very symmetric. Heavy thunderstorm activity is lacking on the southeast side, where 10 knots of wind shear is driving dry air into the circulation. The center is surrounded by a ring of echoes now, which was not the case on Sunday. However, the echoes are weak. The 8:30 am center report from the Hurricane Hunters reported about half of a ragged eyewall, but the 9:15 am report did not mention any evidence of an eyewall. Isaac will have to form an eyewall in order to intensify significantly.


Figure 1. Morning satellite image of Isaac. Note the lack of heavy thunderstorm activity on the storm's southeast side, where dry air and wind shear are combining to interfere with development.

Isaac's rains
Isaac's heaviest rains have fallen along a swath from the east coast of Florida near West Palm Beach to the center of the state, just south of Orlando. West Palm Beach received 7.57" of rain from Isaac as of 10 am EDT this morning. A trained spotter in Western Boynton Beach reported 10" of rain from midnight to midnight Sunday. Heavy rains from Isaac are lingering over Cuba but have ended in Haiti and the Dominican Republic; flash floods in Haiti from Isaac's torrential rains killed at least nineteen, and two died in the Dominican Republic.


Figure 2. Radar-estimated rainfall from Melbourne, Florida radar shows that Isaac has dumped a wide swath of 3+ inches of rain (orange colors) across the state.

Latest model runs for Isaac
The latest set of 0Z and 06Z (8 pm and 2 am EDT) model runs are fairly unified taking Isaac ashore near Southeast Louisiana late Tuesday night or early Wednesday morning, but continue to show major differences in what happens after that. It is still uncertain if a trough of low pressure passing to the north of Isaac will be able to turn the storm due north, as the ECMWF model is predicting, or bypass the storm, allowing a more west-northwest motion into western Louisiana, like the GFS model is predicting. In either case, Isaac is likely to slow down as it approaches the coast, which will increase the damage potential fro m its wind, storm surge, and rains. The latest 8-day precipitation forecast from the GFS model calls for 10 - 20 inches of rain over much of Louisiana. The ECMWF model predicts that these heavy rains will fall more over Mississippi. It appears likely that Arkansas will see some heavy rains from Isaac late in the week, which would help put a dent in the exceptional drought conditions there.


Figure 3. Predicted precipitation for the 8-day period from 2 am Monday August 27 to 2 am Tuesday September 4, from the 2 am EDT August 27 run of the GFS model. This model is predicting a wide swath of 5 - 10 inches of rain (orange colors) will affect portions of Louisiana. Additional very heavy rains are predicted for the Midwest, as moisture from Isaac interacts with a cold front. Image credit: NOAA/NCEP.

Intensity forecast for Isaac
Isaac is currently crossing over a relatively cool eddy of water, which will keep intensification slow today. By tonight, the total heat content of the waters increases, which should aid intensification. Low wind shear of 10 knots or less is likely until landfall. An analysis of upper level winds from the University of Wisconsin CIMSS shows that upper-level outflow to the north is not as strong as yesterday, which should also slow intensification today. The models forecast the upper-level outflow should improve by Tuesday. A storm this large will have trouble undergoing rapid intensification, and Isaac's most likely intensity at landfall will be as a Category 1 hurricane, which is what most of the intensity models are forecasting.


Figure 4. Track of Hurricane Gustav of 2008, which followed a path very similar to that of Isaac's predicted path.

Storm surge forecast for Isaac
Storm surge is the primary damage threat from Isaac. Isaac is a huge storm, with tropical storm-force winds that extend out 205 miles from the center. For comparison, Hurricane Katrina at landfall had tropical storm-force winds that extended out 230 miles from its center. Isaac's large size will enable it to set a large area of the ocean into motion, which will generate a large storm surge once the storm approaches land on the Gulf Coast. Water levels at Shell Beach, Louisiana, just east of New Orleans, were already elevated by 1' this morning. Conversely, water levels have fallen by 2' this morning at St. Petersburg, Florida, where strong offshore winds due to Isaac's counter-clockwise circulation have carried water away from the coast. The latest 6:30 am EDT Integrated Kinetic Energy analysis from NOAA's Hurricane Research Division put the destructive potential of Isaac's winds near 0.6 on a scale of 0 to 6, but the destructive potential of Isaacs's storm surge was 2.1 on a scale of 0 to 6. I expect this destructive potential will rise above 3 by time Isaac makes landfall, making Isaac's storm surge similar to that generated by Category 2 Hurricane Gustav of 2008, which followed a path very similar to Isaac's predicted path. Gustav brought a storm surge characteristic of a Category 1 hurricane to New Orleans: 9.5' to Lake Borgne on the east side of the city. A higher Category 2-scale surge occurred along the south-central coast of Louisiana, and was 12.5' high in Black Bay, forty miles southeast of New Orleans. Recent model runs indicate Isaac may slow down to a forward speed under 5 mph on Tuesday evening and Wednesday morning, close to the coast. If Isaac is just offshore at this time, the coasts of Southeast Louisiana, Mississippi, Alabama, and the Florida Panhandle will be exposed to a large storm surge with battering waves for two high tide cycles. This sort of extending pounding will be capable of delivering more damage than the storm surge of Hurricane Gustav of 2008.

The affect of storm size and angle of approach on storm surge
A 2008 paper by Irish et al., The influence of storm size on hurricane surge, found that large storms like Isaac are capable to delivering a 30% larger storm surge to the coast than a smaller storm with the same maximum wind speeds. The angle with which the storm hit the coast is important, too--a storm moving due north or slightly east of north will deliver a storm surge about 10% greater than a storm moving NNW or NW. Consult our Storm Surge pages for detailed information on what the risk is for the coast. I expect that Isaac's storm surge will be about 30% higher than the typical surge one would expect based on the maximum wind speeds.

Isaac's storm surge will provide the first test of the newly-completed New Orleans levee system upgrade. In the wake of the disastrous storm surge flooding from Hurricane Katrina in 2005, Congress appropriated $14.5 billion to upgrade the New Orleans levee system to withstand a Category 3 hurricane storm surge. Katrina was a Category 3 storm at landfall, but the storm passed far enough to the east of the city that its storm surge was characteristic of a Category 1 - 2 storm at the places where the city's flood walls and levees failed. The new flood defenses were only partially completed in time for the arrival of Hurricane Gustav in 2008, which hit Central Louisiana as a Category 2 storm. Gustav brought a storm surge characteristic of a Category 1 hurricane to New Orleans: 9.5' to Lake Borgne on the east side of the city. Since that time, the imposing 2-mile long IHNC Flood Barrier has been completed to block off the funnel-shaped pair of canals on the east side of the city. I expect New Orleans' new flood defenses will be able to hold back Isaac's surge, but areas outside the levees are at risk of heavy storm surge damage.


Figure 5. A portion of New Orleans' new $14.5 billion dollar flood defenses, as taken from an Army Corps of Engineers map.

New Orleans flood defense info
Army Corps of Engineers map of the new flood defenses
Army Corps of Engineers video showing the flood defenses
New York Times article, Vast Defenses Now Shielding New Orleans

Invest 97L off the coast of Africa
A tropical wave (Invest 97L) is located in the Middle Atlantic, about 1050 miles west-northwest of the Cape Verde Islands. The storm has a modest amount of spin and heavy thunderstorms, and is under moderate wind shear. In their 8 am EDT Tropical Weather Outlook, NHC gave 97L a 30% chance of developing by Wednesday morning. None of the reliable models foresee that 97L will be a threat to the Lesser Antilles Islands, and high wind shear should begin to tear the disturbance apart on Tuesday.

Another tropical wave that moved off the coast of Africa on Sunday is located just south of the Cape Verde Islands. This disturbance is moving west at 10 - 15 mph, and could arrive in the Lesser Antilles around September 2. Several models develop the disturbance into a tropical depression late this week, and NHC is giving the disturbance a 10% chance of becoming a tropical depression by Wednesday morning.

Angela Fritz will have a new post here by 6 pm EDT. I'm in Atlanta to help out The Weather Channel with their on-air hurricane coverage, and will doing a few 3-minute tropical updates at 30 minutes past the hour between 2:30 - 7:30 pm EDT today.

Jeff Masters

Tropical Storm Isaac (chelina)
View from the north side of the Sunshine Skyway Bridge.
Tropical Storm Isaac
our street at noon today (seflagamma)
Aug 26, 2012: Isaac floods our street really bad. Now nearly 11
our street at noon today

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Quoting TallyWeather15:
What is the chance that Tallahassee will get 30 mph winds tommorow? School busses can't drive in it


WTH yall do during strong cold fronts?
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808. Caner
Quoting tennisgirl08:
Can someone post the latest CMC and/or HWRF 12Z runs??


Link

Link
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Quoting TheDewd:
Link

Looks like W motion to me. Anyone care to help me understand why it's WNW or NW?


You are probably observing the fast expanding CDO, and convection mentioned earlier quickly developing on the west side of Isaac, giving the illusion of a west move.
Member Since: July 4, 2005 Posts: 204 Comments: 8871
Quoting LurkyMcLurkerson:
Been reading for a long time here, and have watched since everybody here screaming murder about Katrina, but I usually haven't said a thing.

But would really love to hear somebody who knows stuff comment on what's going on with the blob over FL right now. To my amateur eye, it looks like Isaac gave up on dragging that whole chunk of mess up to his NE along -- there's a little overall pull at the band down around Cuba, but the NE blobby stuff seems more and more like it's responding to something _other_ than Isaac now that's keeping it semi-stationary -- stuff to its W looks more like filling in than real movement of the blob itself.

So now he's strengthening and tightening up a bit, while that blob looks like it's sort of doing its own nasty thing over there.

Again, though, I can just go with what I see, as somebody with only very basic knowledge about any of it. Is there any reason to think that stuff over FL right now is not becoming pretty much disconnected from Isaac as he moves out west?
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Quoting LurkyMcLurkerson:
Been reading for a long time here, and have watched since everybody here screaming murder about Katrina, but I usually haven't said a thing.

But would really love to hear somebody who knows stuff comment on what's going on with the blob over FL right now. To my amateur eye, it looks like Isaac gave up on dragging that whole chunk of mess up to his NE along -- there's a little overall pull at the band down around Cuba, but the NE blobby stuff seems more and more like it's responding to something _other_ than Isaac now that's keeping it semi-stationary -- stuff to its W looks more like filling in than real movement of the blob itself.

So now he's strengthening and tightening up a bit, while that blob looks like it's sort of doing its own nasty thing over there.

Again, though, I can just go with what I see, as somebody with only very basic knowledge about any of it. Is there any reason to think that stuff over FL right now is not becoming pretty much disconnected from Isaac as he moves out west?

I wouldn't be concerned about that - it is being sustained by the upper-level flow caused by Isaac, combined with the lower-level inflow of moisture, also caused by Isaac.

Right now, a vast majority of the focus is on Isaac.
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Quoting dmh1026:
I wonder how that guy in Ft. Lauderdale is feeling with his statement that "This is nuttin, not even a good tropical storm" yesterday?

Hmmm well lets see i am just south of ft lauderdale about a mile from the beach and we got slammed..
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What is the chance that Tallahassee will get 30 mph winds tommorow? School busses can't drive in it
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800. Skyepony (Mod)
Quoting Az4:
Please pardon my ignorance, but is there any way to tell which models are which on the Wunderground Map?

Thank you.


If in wundermap, click on models on the right. A drop down comes up. GFS is default but you can select the model in the drop down.
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posting this for Patrap who is on vaca
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Ok I am back up....so last night the rain was a nusiance and the wind was actually kind of cool but then about 1030pm the electric went out and it started to get unbearably hot. Finally after opening all the windows(not necessarily a good idea with the high winds) and opened the doors kids brought the air mattress to the living room and we all tried to go to sleep...yea right...lol ok so around 330am the lights went back on and then it started to look like Beirut outside with transformers blowing and the sky lit up like day time. Ironically the lights stayed on. This morning about 930 fpl was on the job turned off the electric so that they could fix all the fallen wires. In the mean time my modem fried during a surge I believe and Att just left and brought me a new and improved modem.... Now it is raining like cats and dogs outside and it does not want to seem to stop.
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Quoting txbullseye:


I am on the TX/LA border and i think it will be really close also.


I'm NOT on the TX/LA border, and I still think it will be a very close call.
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Can someone post the latest CMC and/or HWRF 12Z runs??
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Correct me if I am wrong, but wouldn't Isaac have to move NNW at this point to make it to NOLA?
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Quoting atmosweather:


I cannot see them upgrading Isaac to a hurricane just because of a couple of SFMR readings that may or may not be representative of the overall maximum winds, while also not finding any flight level winds at hurricane strength.


They haven't found flight level winds that support anything over 60mph though, NHC still upped the winds to 70mph per ATCF. Might have a hurricane on our hands soon, just might.
Member Since: July 8, 2005 Posts: 259 Comments: 24016
Quoting DavidHOUTX:
]

It may not even hit any one of them. I still think this is a TX/LA border storm. Just my opinion though


I am on the TX/LA border and i think it will be really close also.
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Recon now heading straight north and will come back to the centre fro the NE.

This is the interesting bit.
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Quoting LurkyMcLurkerson:
Been reading for a long time here, and have watched since everybody here screaming murder about Katrina, but I usually haven't said a thing.

But would really love to hear somebody who knows stuff comment on what's going on with the blob over FL right now. To my amateur eye, it looks like Isaac gave up on dragging that whole chunk of mess up to his NE along -- there's a little overall pull at the band down around Cuba, but the NE blobby stuff seems more and more like it's responding to something _other_ than Isaac now that's keeping it semi-stationary -- stuff to its W looks more like filling in than real movement of the blob itself.

So now he's strengthening and tightening up a bit, while that blob looks like it's sort of doing its own nasty thing over there.

Again, though, I can just go with what I see, as somebody with only very basic knowledge about any of it. Is there any reason to think that stuff over FL right now is not becoming pretty much disconnected from Isaac as he moves out west?
yes ive been asking the same question, right now i dont think anyone knows, but there are some watching it closely, thanks for bringing it up
Member Since: August 6, 2011 Posts: 4 Comments: 38424
Link

Looks like W motion to me. Anyone care to help me understand why it's WNW or NW?
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Quoting kmanislander:


It would appear so. The dry slot can be seen in this image almost closed off which should enable the storm to build an eyewall very soon assuming no deterioration in the current trend. The faster winds are allowing the system to wrap the convection all the way around the center.

This is a strengthening storm that could see winds jump 10 to 15 MPH within two to three hours IMO.



As it has been noted on here before about Isaac's pour inner core and circulation problems in the past... I believe we are now seeing how the Northeast Gulf of Mexico geographical layout can aid in the development of a storms circulation. Similar to what BOC storms experience, only not quit as pronounced since BOC has 3 sided landmass, while the NE gulf is just two sided. Still you got to think that the geographical layout of Florida and the NE gulf Coast only helped Isaac tighten is core up, as we've seen today.

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788. Caner
Quoting trHUrrIXC5MMX:



The color of the track matches the color of their name on the legend...

/at a loss.
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Isaac has also been moving due west over the last few hours, this could make Isaac spend quite a bit more time over the warm waters of the GOM.
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Quoting LurkyMcLurkerson:
Been reading for a long time here, and have watched since everybody here screaming murder about Katrina, but I usually haven't said a thing.

But would really love to hear somebody who knows stuff comment on what's going on with the blob over FL right now. To my amateur eye, it looks like Isaac gave up on dragging that whole chunk of mess up to his NE along -- there's a little overall pull at the band down around Cuba, but the NE blobby stuff seems more and more like it's responding to something _other_ than Isaac now that's keeping it semi-stationary -- stuff to its W looks more like filling in than real movement of the blob itself.

So now he's strengthening and tightening up a bit, while that blob looks like it's sort of doing its own nasty thing over there.

Again, though, I can just go with what I see, as somebody with only very basic knowledge about any of it. Is there any reason to think that stuff over FL right now is not becoming pretty much disconnected from Isaac as he moves out west?
Been asking for answers from someone on that blop for a couple of hours!!!
Member Since: August 21, 2011 Posts: 0 Comments: 143
Raining at 3-5 inches/hour here in Greenacres (W Palm Beach). Areas that had drained before, are now flooded again. At this rate my 2nd floor apartment will be the new 1st floor.
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Isaac is just a few clicks away on the current forecast points from where he was supposed to reach hurricane strength so this part of the forecast appears to be on track based on satt loop appearance.
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783. Skyepony (Mod)
FL has seemed to have finally severed that extra something that Isaac pulled into itself back in the Central Atlantic, that had it looking like two entities that couldn't quite come together into one at times... Between that hindrance being removed & the loop eddy he's over some intensifying could be next up..

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Quoting Az4:
Please pardon my ignorance, but is there any way to tell which models are which on the Wunderground Map?

Thank you.

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Quoting Beachfoxx:
Did you take a photo of the rainbow?????
No but a friend of mine did that lives nearby. She put it on FB I'll share it on my page Beach :)
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Quoting GetReal:


I have to agree with the earlier analysis posted by MLC. Isaac is now feeling the warmer waters of the Gulf Loop, as evidence observe the LARGE and expanding feeder band forming on the NW & W sides of the system. That feeder band is currently wrapping around to the south and east sides of Isaac, and will block further intrusions of dry air from the south.

I am prepared to eat the crow, but I am confident that Isaac will be upgraded to a strengthening CAT 1 hurricane on the next advisory.


I see a thousand power lines down all over the Gulf Coast......
Member Since: June 16, 2006 Posts: 0 Comments: 1565
Quoting kmanislander:


Cat 1 very soon as I said a little while ago. Will likely come with the mission currently being flown if they do several more center passes.


KMAN, your thoughts on track?
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Quoting atmosweather:


I cannot see them upgrading Isaac to a hurricane just because of a couple of SFMR readings that may or may not be representative of the overall maximum winds, while also not finding any flight level winds at hurricane strength.


I don't disagree, but we do still have two hours or so before the next advisory. That's why I say it'll be interesting.
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777. Az4
Please pardon my ignorance, but is there any way to tell which models are which on the Wunderground Map?

Thank you.
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meanwhile in the EPAC we have TD 9E
possibly Ileana

EP, 09, 2012082718, , BEST, 0, 149N, 1065W, 30, 1006, TD
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Been reading for a long time here, and have watched since everybody here screaming murder about Katrina, but I usually haven't said a thing.

But would really love to hear somebody who knows stuff comment on what's going on with the blob over FL right now. To my amateur eye, it looks like Isaac gave up on dragging that whole chunk of mess up to his NE along -- there's a little overall pull at the band down around Cuba, but the NE blobby stuff seems more and more like it's responding to something _other_ than Isaac now that's keeping it semi-stationary -- stuff to its W looks more like filling in than real movement of the blob itself.

So now he's strengthening and tightening up a bit, while that blob looks like it's sort of doing its own nasty thing over there.

Again, though, I can just go with what I see, as somebody with only very basic knowledge about any of it. Is there any reason to think that stuff over FL right now is not becoming pretty much disconnected from Isaac as he moves out west?
Member Since: August 26, 2012 Posts: 0 Comments: 368
774. Caner
This Flash animation with the "Thunderstorm Color Curve" enhancement applied reveals low cloud tops within a forming eye.

Link
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773. Hugo5
Don't think anyone is watching, but some of these storms in TEXAS need a watch or warning soon. Sitting in Killeen watching the one over head now got some rotation on the south side.
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Quoting moonlightcowboy:


Agreed. Good to see you, Kman! Missed your commentary.


Hi there.

I was on vacation in Ruidoso playing some of those mountain courses. Fabulous terrain and views at 8000 feet.
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Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 27th day of the month at 18:26Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 27
Observation Number: 06
A. Time of Center Fix: 27th day of the month at 17:52:10Z
B. Center Fix Coordinates: 26°07'N 85°59'W (26.1167N 85.9833W)
B. Center Fix Location: 252 miles (405 km) to the WSW (239°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: 1,296m (4,252ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 64kts (~ 73.6mph)
E. Location of the Estimated Maximum Surface Wind: 40 nautical miles (46 statute miles) to the NW (318°) of center fix
F. Maximum Flight Level Wind Inbound: From 57° at 54kts (From the ENE at ~ 62.1mph)
G. Location of Maximum Flight Level Wind Inbound: 37 nautical miles (43 statute miles) to the NW (319°) of center fix
H. Minimum Sea Level Pressure: 985mb (29.09 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 18°C (64°F) at a pressure alt. of 1,538m (5,046ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,544m (5,066ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 0.5 nautical miles
Remarks Section:
Maximum Flight Level Wind: 54kts (~ 62.1mph) in the northwest quadrant at 17:39:00Z

according to this Isaac just about at the hurricane threshold.
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Quoting MiamiHurricanes09:
Hopefully it's still Stewart's shift throughout the remainder of the afternoon lol. :P


How about the next three days?

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Quoting RitaEvac:
Track can move another 100 miles west, SE TX still would be in the clear


Not at this time, but it could later after it makes landfall... depending on the C CONUS High position.
Member Since: August 14, 2008 Posts: 4 Comments: 4972
Did you take a photo of the rainbow?????
Quoting tkeith:
You can see it from here too .
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Quoting MiamiHurricanes09:
Hopefully it's still Stewart's shift throughout the remainder of the afternoon lol. :P


Doubt it. Will most likely be Pasch and he'll write two sentences before he gets tired.
Member Since: July 15, 2006 Posts: 17 Comments: 10244
Alot can be said for buoy reports....

As the eye so called eye crossed buoy 42003 it reported winds of only 44kts ....then calm then 36kts....with 17ft waves.....

Thanks for Dry Air and ULLs ....this thing could have been huge if it wouldn't have run into these buzz saws......Grateful for that....isaac will not be one of those "i" storms to have it's name retired....unless flooding of huge proportions happens the next 7days.....oh and it could!!!
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I have to agree with the earlier analysis posted by MLC. Isaac is now feeling the warmer waters of the Gulf Loop, as evidence observe the LARGE and expanding feeder band forming on the NW & W sides of the system. That feeder band is currently wrapping around to the south and east sides of Isaac, and will block further intrusions of dry air from the south.

I am prepared to eat the crow, but I am confident that Isaac will be upgraded to a strengthening CAT 1 hurricane on the next advisory.
Member Since: July 4, 2005 Posts: 204 Comments: 8871
Quoting 7544:
east fla getting hammerd from issac tail that broke off more to come wasnt this very unexpected looks like their even getting ts conditions from the post on here they keep expanding the flood warning went from 6pm to 8pm now till 1030 pm stay safe all hope your pwer stays on to keep us update from your local areas


St Augustine got some wind and alot of rain. Thas why I want to pick up the yard tuesday.

I found this usefull, from the weather chanel

These are the pressure ranges in millibars typically associated with hurricanes:

Cat 1 980-993
Cat 2 965-979
Cat 3 945-964
Cat 4 920-944
Cat 5 <920
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Quoting Bitmap7:


So at/near cat1? The pressure also seems to have gone up a bit at 985mb fromm 984mb.


Cat 1 very soon as I said a little while ago. Will likely come with the mission currently being flown if they do several more center passes.
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Folks..IF you are flooding or see bad flooding..dont assume your local govt knows about it..phone it in and let them know whats happening ok...
Member Since: August 6, 2011 Posts: 4 Comments: 38424
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Almost.

Member Since: July 15, 2006 Posts: 17 Comments: 10244
Quoting moonlightcowboy:
There is an AMAZING phenomenon in the sky right now over south MS.

BE VERY CAREFUL - DO NOT LOOK RIGHT AT THE SUN!!! But, put your hands together to form a flat triangle to cover as you extend your arms up towards the sun.

Then look all the way around the sun, a FULL CIRCULAR RAINBOW around the sun! Awesome! :) But be careful for your eye's safety.


Ice crystals in the upper atmosphere? The cirrus overcast from ISAAC?
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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